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MELSEC-
A
12 CONTROL AUXILIARY FUNCTIONS
(2) Relation between the movement amount per pulse and speed
The following shows the relation of the "movement amount per pulse (A)" to the
command speed and actual speed. The command speed is the speed
commanded by each control, and the actual speed is the actual feedrate.
Command speed = V (The command frequency at that time is represented by "f")
Actual speed = V' (The command frequency at that time is represented by " f' ")
Relation of the command speed and actual speed
1) Movement amount per pulse < 1
V < V
' (f < f')
The actual speed becomes faster than the
command speed.
2) Movement amount per pulse = 1
V = V
' (f = f')
The actual speed is the same as the command
speed.
3) Movement amount per pulse > 1
V > V
' (f > f')
The actual speed becomes slower than the
command speed.
Command speed V
V
2)
1)
3)
Actual speed V'
t
Fig. 12.9 Relation of the movement amount per pulse to the command speed and actual speed